ClientLogin authentication support for the AdWords API and the DoubleClick Ad Exchange API will sunset along with v201309 on July 21st, 2014. You only have 3 weeks left to migrate!

We have plenty of resources to help you migrate. It might take longer than you expect to migrate to OAuth 2.0, especially if you don't already use a single top-level MCC to manage your AdWords accounts or if you are a DoubleClick Ad Exchange customer.